Valid xmls are incorrectly marked as invalid due to warnings being treated as errors

[melatal]

Valid Invoices are being incorrectly flagged as invalid because the validator is treating warnings as errors.
This causes false negatives where properly formatted files that contain minor issues (warnings) are rejected.

Specific Example
Validation Rule: [CII-SR-351]
Message: "InvoiceeTradeParty should not be present"
Rule Type: Schematron Warning (SHOULD NOT, not MUST NOT)
Current Behavior: Treated as ERROR → File marked as INVALID
Expected Behavior: Treated as WARNING → File marked as VALID (with warning)

Actual Result
schema validation fails:org.xml.sax.SAXParseException; lineNumber: 4; columnNumber: 51400; cvc-complex-type.2.4.a: Invalid content was found starting with element '{"urn:un:unece:uncefact:data:standard:ReusableAggregateBusinessInformationEntity:100":InvoiceeTradeParty}'. One of '{"urn:un:unece:uncefact:data:standard:ReusableAggregateBusinessInformationEntity:100":PayeeTradeParty, "urn:un:unece:uncefact:data:standard:ReusableAggregateBusinessInformationEntity:100":SpecifiedTradeSettlementPaymentMeans, "urn:un:unece:uncefact:data:standard:ReusableAggregateBusinessInformationEntity:100":ApplicableTradeTax}' is expected.
Severity: Error

[CII-SR-351] - InvoiceeTradeParty should not be present [ID CII-SR-351] from /xslt/en16931schematron/EN16931-CII-validation.xslt)
Location: /:CrossIndustryInvoice[namespace-uri()='urn:un:unece:uncefact:data:standard:CrossIndustryInvoice:100'][1]/:SupplyChainTradeTransaction[namespace-uri()='urn:un:unece:uncefact:data:standard:CrossIndustryInvoice:100'][1]/*:ApplicableHeaderTradeSettlement[namespace-uri()='urn:un:unece:uncefact:data:standard:ReusableAggregateBusinessInformationEntity:100'][1]
Severity: Warning

[jstaerk]

Please submit an example. AFAIK there is only a handful of warnings in ZUGFeRD yet (and somebody even tested) but if thats true we need to reproduce and upstream

[melatal]

Hi, Here is an example file that should fire a warning but returns an error.
01.01a-INVOICE_uncefact.xml